Backup is needed in company for disaster recovery purpose and provide availability data so can achieve one of principle of information security also known as CIA Triad.
Basic of common backup process :
1. Full Backup : Backup all data that have selected.
2. Incremental Backup : Backup all data or files changed since last backup (any kind of backup such as full, incremental or differential).
3. Differential Backup : Backup all data or files changed since last full backup
there are 2 backup rotation method :
Most common use for backup schedule and also Known as GFS. GFS using 3 generation of tapes. incremental backup is son, Weekly Full Backup is father and Monthly Full Backup is GrandFather.
firstly : One to four media is set for incremental backup, performed daily from Monday to thursday. 4 media set referred as son media set.
secondly : New media set performed weekly full backup started on friday, and not performed incremental backup. Media set used referred as father media set.
thirdly : New media set performed monthly full backup on the last friday of the month.Media set used referred as grandfather media set. Grandfather tape stored off-site while younger generations in backup rotation.
2. Tower of hanoi
This method is more complex and based on mathematical puzzle. The game consists of three pegs with a number of discs placed on one of them. Each disc is of its own size and the smaller discs are placed on the larger ones. The task is to move the discs to another peg moving only one disc at a time and only placing a smaller disc on a larger one.
still in update progress… i will explain later.